1 /*
2 *  Digi AccelePort USB-4 and USB-2 Serial Converters
3 *
4 *  Copyright 2000 by Digi International
5 *
6 *  This program is free software; you can redistribute it and/or modify
7 *  it under the terms of the GNU General Public License as published by
8 *  the Free Software Foundation; either version 2 of the License, or
9 *  (at your option) any later version.
10 *
11 *  Shamelessly based on Brian Warner's keyspan_pda.c and Greg Kroah-Hartman's
12 *  usb-serial driver.
13 *
14 *  Peter Berger (pberger@brimson.com)
15 *  Al Borchers (borchers@steinerpoint.com)
16 */
17 
18 #include <linux/kernel.h>
19 #include <linux/errno.h>
20 #include <linux/init.h>
21 #include <linux/slab.h>
22 #include <linux/tty.h>
23 #include <linux/tty_driver.h>
24 #include <linux/tty_flip.h>
25 #include <linux/module.h>
26 #include <linux/spinlock.h>
27 #include <linux/workqueue.h>
28 #include <linux/uaccess.h>
29 #include <linux/usb.h>
30 #include <linux/wait.h>
31 #include <linux/usb/serial.h>
32 
33 /* Defines */
34 
35 #define DRIVER_AUTHOR "Peter Berger <pberger@brimson.com>, Al Borchers <borchers@steinerpoint.com>"
36 #define DRIVER_DESC "Digi AccelePort USB-2/USB-4 Serial Converter driver"
37 
38 /* port output buffer length -- must be <= transfer buffer length - 2 */
39 /* so we can be sure to send the full buffer in one urb */
40 #define DIGI_OUT_BUF_SIZE		8
41 
42 /* port input buffer length -- must be >= transfer buffer length - 3 */
43 /* so we can be sure to hold at least one full buffer from one urb */
44 #define DIGI_IN_BUF_SIZE		64
45 
46 /* retry timeout while sleeping */
47 #define DIGI_RETRY_TIMEOUT		(HZ/10)
48 
49 /* timeout while waiting for tty output to drain in close */
50 /* this delay is used twice in close, so the total delay could */
51 /* be twice this value */
52 #define DIGI_CLOSE_TIMEOUT		(5*HZ)
53 
54 
55 /* AccelePort USB Defines */
56 
57 /* ids */
58 #define DIGI_VENDOR_ID			0x05c5
59 #define DIGI_2_ID			0x0002	/* USB-2 */
60 #define DIGI_4_ID			0x0004	/* USB-4 */
61 
62 /* commands
63  * "INB": can be used on the in-band endpoint
64  * "OOB": can be used on the out-of-band endpoint
65  */
66 #define DIGI_CMD_SET_BAUD_RATE			0	/* INB, OOB */
67 #define DIGI_CMD_SET_WORD_SIZE			1	/* INB, OOB */
68 #define DIGI_CMD_SET_PARITY			2	/* INB, OOB */
69 #define DIGI_CMD_SET_STOP_BITS			3	/* INB, OOB */
70 #define DIGI_CMD_SET_INPUT_FLOW_CONTROL		4	/* INB, OOB */
71 #define DIGI_CMD_SET_OUTPUT_FLOW_CONTROL	5	/* INB, OOB */
72 #define DIGI_CMD_SET_DTR_SIGNAL			6	/* INB, OOB */
73 #define DIGI_CMD_SET_RTS_SIGNAL			7	/* INB, OOB */
74 #define DIGI_CMD_READ_INPUT_SIGNALS		8	/*      OOB */
75 #define DIGI_CMD_IFLUSH_FIFO			9	/*      OOB */
76 #define DIGI_CMD_RECEIVE_ENABLE			10	/* INB, OOB */
77 #define DIGI_CMD_BREAK_CONTROL			11	/* INB, OOB */
78 #define DIGI_CMD_LOCAL_LOOPBACK			12	/* INB, OOB */
79 #define DIGI_CMD_TRANSMIT_IDLE			13	/* INB, OOB */
80 #define DIGI_CMD_READ_UART_REGISTER		14	/*      OOB */
81 #define DIGI_CMD_WRITE_UART_REGISTER		15	/* INB, OOB */
82 #define DIGI_CMD_AND_UART_REGISTER		16	/* INB, OOB */
83 #define DIGI_CMD_OR_UART_REGISTER		17	/* INB, OOB */
84 #define DIGI_CMD_SEND_DATA			18	/* INB      */
85 #define DIGI_CMD_RECEIVE_DATA			19	/* INB      */
86 #define DIGI_CMD_RECEIVE_DISABLE		20	/* INB      */
87 #define DIGI_CMD_GET_PORT_TYPE			21	/*      OOB */
88 
89 /* baud rates */
90 #define DIGI_BAUD_50				0
91 #define DIGI_BAUD_75				1
92 #define DIGI_BAUD_110				2
93 #define DIGI_BAUD_150				3
94 #define DIGI_BAUD_200				4
95 #define DIGI_BAUD_300				5
96 #define DIGI_BAUD_600				6
97 #define DIGI_BAUD_1200				7
98 #define DIGI_BAUD_1800				8
99 #define DIGI_BAUD_2400				9
100 #define DIGI_BAUD_4800				10
101 #define DIGI_BAUD_7200				11
102 #define DIGI_BAUD_9600				12
103 #define DIGI_BAUD_14400				13
104 #define DIGI_BAUD_19200				14
105 #define DIGI_BAUD_28800				15
106 #define DIGI_BAUD_38400				16
107 #define DIGI_BAUD_57600				17
108 #define DIGI_BAUD_76800				18
109 #define DIGI_BAUD_115200			19
110 #define DIGI_BAUD_153600			20
111 #define DIGI_BAUD_230400			21
112 #define DIGI_BAUD_460800			22
113 
114 /* arguments */
115 #define DIGI_WORD_SIZE_5			0
116 #define DIGI_WORD_SIZE_6			1
117 #define DIGI_WORD_SIZE_7			2
118 #define DIGI_WORD_SIZE_8			3
119 
120 #define DIGI_PARITY_NONE			0
121 #define DIGI_PARITY_ODD				1
122 #define DIGI_PARITY_EVEN			2
123 #define DIGI_PARITY_MARK			3
124 #define DIGI_PARITY_SPACE			4
125 
126 #define DIGI_STOP_BITS_1			0
127 #define DIGI_STOP_BITS_2			1
128 
129 #define DIGI_INPUT_FLOW_CONTROL_XON_XOFF	1
130 #define DIGI_INPUT_FLOW_CONTROL_RTS		2
131 #define DIGI_INPUT_FLOW_CONTROL_DTR		4
132 
133 #define DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF	1
134 #define DIGI_OUTPUT_FLOW_CONTROL_CTS		2
135 #define DIGI_OUTPUT_FLOW_CONTROL_DSR		4
136 
137 #define DIGI_DTR_INACTIVE			0
138 #define DIGI_DTR_ACTIVE				1
139 #define DIGI_DTR_INPUT_FLOW_CONTROL		2
140 
141 #define DIGI_RTS_INACTIVE			0
142 #define DIGI_RTS_ACTIVE				1
143 #define DIGI_RTS_INPUT_FLOW_CONTROL		2
144 #define DIGI_RTS_TOGGLE				3
145 
146 #define DIGI_FLUSH_TX				1
147 #define DIGI_FLUSH_RX				2
148 #define DIGI_RESUME_TX				4 /* clears xoff condition */
149 
150 #define DIGI_TRANSMIT_NOT_IDLE			0
151 #define DIGI_TRANSMIT_IDLE			1
152 
153 #define DIGI_DISABLE				0
154 #define DIGI_ENABLE				1
155 
156 #define DIGI_DEASSERT				0
157 #define DIGI_ASSERT				1
158 
159 /* in band status codes */
160 #define DIGI_OVERRUN_ERROR			4
161 #define DIGI_PARITY_ERROR			8
162 #define DIGI_FRAMING_ERROR			16
163 #define DIGI_BREAK_ERROR			32
164 
165 /* out of band status */
166 #define DIGI_NO_ERROR				0
167 #define DIGI_BAD_FIRST_PARAMETER		1
168 #define DIGI_BAD_SECOND_PARAMETER		2
169 #define DIGI_INVALID_LINE			3
170 #define DIGI_INVALID_OPCODE			4
171 
172 /* input signals */
173 #define DIGI_READ_INPUT_SIGNALS_SLOT		1
174 #define DIGI_READ_INPUT_SIGNALS_ERR		2
175 #define DIGI_READ_INPUT_SIGNALS_BUSY		4
176 #define DIGI_READ_INPUT_SIGNALS_PE		8
177 #define DIGI_READ_INPUT_SIGNALS_CTS		16
178 #define DIGI_READ_INPUT_SIGNALS_DSR		32
179 #define DIGI_READ_INPUT_SIGNALS_RI		64
180 #define DIGI_READ_INPUT_SIGNALS_DCD		128
181 
182 
183 /* Structures */
184 
185 struct digi_serial {
186 	spinlock_t ds_serial_lock;
187 	struct usb_serial_port *ds_oob_port;	/* out-of-band port */
188 	int ds_oob_port_num;			/* index of out-of-band port */
189 	int ds_device_started;
190 };
191 
192 struct digi_port {
193 	spinlock_t dp_port_lock;
194 	int dp_port_num;
195 	int dp_out_buf_len;
196 	unsigned char dp_out_buf[DIGI_OUT_BUF_SIZE];
197 	int dp_write_urb_in_use;
198 	unsigned int dp_modem_signals;
199 	int dp_transmit_idle;
200 	wait_queue_head_t dp_transmit_idle_wait;
201 	int dp_throttled;
202 	int dp_throttle_restart;
203 	wait_queue_head_t dp_flush_wait;
204 	wait_queue_head_t dp_close_wait;	/* wait queue for close */
205 	struct work_struct dp_wakeup_work;
206 	struct usb_serial_port *dp_port;
207 };
208 
209 
210 /* Local Function Declarations */
211 
212 static void digi_wakeup_write_lock(struct work_struct *work);
213 static int digi_write_oob_command(struct usb_serial_port *port,
214 	unsigned char *buf, int count, int interruptible);
215 static int digi_write_inb_command(struct usb_serial_port *port,
216 	unsigned char *buf, int count, unsigned long timeout);
217 static int digi_set_modem_signals(struct usb_serial_port *port,
218 	unsigned int modem_signals, int interruptible);
219 static int digi_transmit_idle(struct usb_serial_port *port,
220 	unsigned long timeout);
221 static void digi_rx_throttle(struct tty_struct *tty);
222 static void digi_rx_unthrottle(struct tty_struct *tty);
223 static void digi_set_termios(struct tty_struct *tty,
224 		struct usb_serial_port *port, struct ktermios *old_termios);
225 static void digi_break_ctl(struct tty_struct *tty, int break_state);
226 static int digi_tiocmget(struct tty_struct *tty);
227 static int digi_tiocmset(struct tty_struct *tty, unsigned int set,
228 		unsigned int clear);
229 static int digi_write(struct tty_struct *tty, struct usb_serial_port *port,
230 		const unsigned char *buf, int count);
231 static void digi_write_bulk_callback(struct urb *urb);
232 static int digi_write_room(struct tty_struct *tty);
233 static int digi_chars_in_buffer(struct tty_struct *tty);
234 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port);
235 static void digi_close(struct usb_serial_port *port);
236 static void digi_dtr_rts(struct usb_serial_port *port, int on);
237 static int digi_startup_device(struct usb_serial *serial);
238 static int digi_startup(struct usb_serial *serial);
239 static void digi_disconnect(struct usb_serial *serial);
240 static void digi_release(struct usb_serial *serial);
241 static int digi_port_probe(struct usb_serial_port *port);
242 static int digi_port_remove(struct usb_serial_port *port);
243 static void digi_read_bulk_callback(struct urb *urb);
244 static int digi_read_inb_callback(struct urb *urb);
245 static int digi_read_oob_callback(struct urb *urb);
246 
247 
248 static const struct usb_device_id id_table_combined[] = {
249 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_2_ID) },
250 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_4_ID) },
251 	{ }						/* Terminating entry */
252 };
253 
254 static const struct usb_device_id id_table_2[] = {
255 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_2_ID) },
256 	{ }						/* Terminating entry */
257 };
258 
259 static const struct usb_device_id id_table_4[] = {
260 	{ USB_DEVICE(DIGI_VENDOR_ID, DIGI_4_ID) },
261 	{ }						/* Terminating entry */
262 };
263 
264 MODULE_DEVICE_TABLE(usb, id_table_combined);
265 
266 /* device info needed for the Digi serial converter */
267 
268 static struct usb_serial_driver digi_acceleport_2_device = {
269 	.driver = {
270 		.owner =		THIS_MODULE,
271 		.name =			"digi_2",
272 	},
273 	.description =			"Digi 2 port USB adapter",
274 	.id_table =			id_table_2,
275 	.num_ports =			3,
276 	.open =				digi_open,
277 	.close =			digi_close,
278 	.dtr_rts =			digi_dtr_rts,
279 	.write =			digi_write,
280 	.write_room =			digi_write_room,
281 	.write_bulk_callback = 		digi_write_bulk_callback,
282 	.read_bulk_callback =		digi_read_bulk_callback,
283 	.chars_in_buffer =		digi_chars_in_buffer,
284 	.throttle =			digi_rx_throttle,
285 	.unthrottle =			digi_rx_unthrottle,
286 	.set_termios =			digi_set_termios,
287 	.break_ctl =			digi_break_ctl,
288 	.tiocmget =			digi_tiocmget,
289 	.tiocmset =			digi_tiocmset,
290 	.attach =			digi_startup,
291 	.disconnect =			digi_disconnect,
292 	.release =			digi_release,
293 	.port_probe =			digi_port_probe,
294 	.port_remove =			digi_port_remove,
295 };
296 
297 static struct usb_serial_driver digi_acceleport_4_device = {
298 	.driver = {
299 		.owner =		THIS_MODULE,
300 		.name =			"digi_4",
301 	},
302 	.description =			"Digi 4 port USB adapter",
303 	.id_table =			id_table_4,
304 	.num_ports =			4,
305 	.open =				digi_open,
306 	.close =			digi_close,
307 	.write =			digi_write,
308 	.write_room =			digi_write_room,
309 	.write_bulk_callback = 		digi_write_bulk_callback,
310 	.read_bulk_callback =		digi_read_bulk_callback,
311 	.chars_in_buffer =		digi_chars_in_buffer,
312 	.throttle =			digi_rx_throttle,
313 	.unthrottle =			digi_rx_unthrottle,
314 	.set_termios =			digi_set_termios,
315 	.break_ctl =			digi_break_ctl,
316 	.tiocmget =			digi_tiocmget,
317 	.tiocmset =			digi_tiocmset,
318 	.attach =			digi_startup,
319 	.disconnect =			digi_disconnect,
320 	.release =			digi_release,
321 	.port_probe =			digi_port_probe,
322 	.port_remove =			digi_port_remove,
323 };
324 
325 static struct usb_serial_driver * const serial_drivers[] = {
326 	&digi_acceleport_2_device, &digi_acceleport_4_device, NULL
327 };
328 
329 /* Functions */
330 
331 /*
332  *  Cond Wait Interruptible Timeout Irqrestore
333  *
334  *  Do spin_unlock_irqrestore and interruptible_sleep_on_timeout
335  *  so that wake ups are not lost if they occur between the unlock
336  *  and the sleep.  In other words, spin_unlock_irqrestore and
337  *  interruptible_sleep_on_timeout are "atomic" with respect to
338  *  wake ups.  This is used to implement condition variables.
339  *
340  *  interruptible_sleep_on_timeout is deprecated and has been replaced
341  *  with the equivalent code.
342  */
343 
344 static long cond_wait_interruptible_timeout_irqrestore(
345 	wait_queue_head_t *q, long timeout,
346 	spinlock_t *lock, unsigned long flags)
347 __releases(lock)
348 {
349 	DEFINE_WAIT(wait);
350 
351 	prepare_to_wait(q, &wait, TASK_INTERRUPTIBLE);
352 	spin_unlock_irqrestore(lock, flags);
353 	timeout = schedule_timeout(timeout);
354 	finish_wait(q, &wait);
355 
356 	return timeout;
357 }
358 
359 
360 /*
361  *  Digi Wakeup Write
362  *
363  *  Wake up port, line discipline, and tty processes sleeping
364  *  on writes.
365  */
366 
367 static void digi_wakeup_write_lock(struct work_struct *work)
368 {
369 	struct digi_port *priv =
370 			container_of(work, struct digi_port, dp_wakeup_work);
371 	struct usb_serial_port *port = priv->dp_port;
372 	unsigned long flags;
373 
374 	spin_lock_irqsave(&priv->dp_port_lock, flags);
375 	tty_port_tty_wakeup(&port->port);
376 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
377 }
378 
379 /*
380  *  Digi Write OOB Command
381  *
382  *  Write commands on the out of band port.  Commands are 4
383  *  bytes each, multiple commands can be sent at once, and
384  *  no command will be split across USB packets.  Returns 0
385  *  if successful, -EINTR if interrupted while sleeping and
386  *  the interruptible flag is true, or a negative error
387  *  returned by usb_submit_urb.
388  */
389 
390 static int digi_write_oob_command(struct usb_serial_port *port,
391 	unsigned char *buf, int count, int interruptible)
392 {
393 	int ret = 0;
394 	int len;
395 	struct usb_serial_port *oob_port = (struct usb_serial_port *)((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
396 	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
397 	unsigned long flags = 0;
398 
399 	dev_dbg(&port->dev,
400 		"digi_write_oob_command: TOP: port=%d, count=%d\n",
401 		oob_priv->dp_port_num, count);
402 
403 	spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
404 	while (count > 0) {
405 		while (oob_priv->dp_write_urb_in_use) {
406 			cond_wait_interruptible_timeout_irqrestore(
407 				&oob_port->write_wait, DIGI_RETRY_TIMEOUT,
408 				&oob_priv->dp_port_lock, flags);
409 			if (interruptible && signal_pending(current))
410 				return -EINTR;
411 			spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
412 		}
413 
414 		/* len must be a multiple of 4, so commands are not split */
415 		len = min(count, oob_port->bulk_out_size);
416 		if (len > 4)
417 			len &= ~3;
418 		memcpy(oob_port->write_urb->transfer_buffer, buf, len);
419 		oob_port->write_urb->transfer_buffer_length = len;
420 		ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
421 		if (ret == 0) {
422 			oob_priv->dp_write_urb_in_use = 1;
423 			count -= len;
424 			buf += len;
425 		}
426 	}
427 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
428 	if (ret)
429 		dev_err(&port->dev, "%s: usb_submit_urb failed, ret=%d\n",
430 			__func__, ret);
431 	return ret;
432 
433 }
434 
435 
436 /*
437  *  Digi Write In Band Command
438  *
439  *  Write commands on the given port.  Commands are 4
440  *  bytes each, multiple commands can be sent at once, and
441  *  no command will be split across USB packets.  If timeout
442  *  is non-zero, write in band command will return after
443  *  waiting unsuccessfully for the URB status to clear for
444  *  timeout ticks.  Returns 0 if successful, or a negative
445  *  error returned by digi_write.
446  */
447 
448 static int digi_write_inb_command(struct usb_serial_port *port,
449 	unsigned char *buf, int count, unsigned long timeout)
450 {
451 	int ret = 0;
452 	int len;
453 	struct digi_port *priv = usb_get_serial_port_data(port);
454 	unsigned char *data = port->write_urb->transfer_buffer;
455 	unsigned long flags = 0;
456 
457 	dev_dbg(&port->dev, "digi_write_inb_command: TOP: port=%d, count=%d\n",
458 		priv->dp_port_num, count);
459 
460 	if (timeout)
461 		timeout += jiffies;
462 	else
463 		timeout = ULONG_MAX;
464 
465 	spin_lock_irqsave(&priv->dp_port_lock, flags);
466 	while (count > 0 && ret == 0) {
467 		while (priv->dp_write_urb_in_use &&
468 		       time_before(jiffies, timeout)) {
469 			cond_wait_interruptible_timeout_irqrestore(
470 				&port->write_wait, DIGI_RETRY_TIMEOUT,
471 				&priv->dp_port_lock, flags);
472 			if (signal_pending(current))
473 				return -EINTR;
474 			spin_lock_irqsave(&priv->dp_port_lock, flags);
475 		}
476 
477 		/* len must be a multiple of 4 and small enough to */
478 		/* guarantee the write will send buffered data first, */
479 		/* so commands are in order with data and not split */
480 		len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
481 		if (len > 4)
482 			len &= ~3;
483 
484 		/* write any buffered data first */
485 		if (priv->dp_out_buf_len > 0) {
486 			data[0] = DIGI_CMD_SEND_DATA;
487 			data[1] = priv->dp_out_buf_len;
488 			memcpy(data + 2, priv->dp_out_buf,
489 				priv->dp_out_buf_len);
490 			memcpy(data + 2 + priv->dp_out_buf_len, buf, len);
491 			port->write_urb->transfer_buffer_length
492 				= priv->dp_out_buf_len + 2 + len;
493 		} else {
494 			memcpy(data, buf, len);
495 			port->write_urb->transfer_buffer_length = len;
496 		}
497 
498 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
499 		if (ret == 0) {
500 			priv->dp_write_urb_in_use = 1;
501 			priv->dp_out_buf_len = 0;
502 			count -= len;
503 			buf += len;
504 		}
505 
506 	}
507 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
508 
509 	if (ret)
510 		dev_err(&port->dev,
511 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
512 			__func__, ret, priv->dp_port_num);
513 	return ret;
514 }
515 
516 
517 /*
518  *  Digi Set Modem Signals
519  *
520  *  Sets or clears DTR and RTS on the port, according to the
521  *  modem_signals argument.  Use TIOCM_DTR and TIOCM_RTS flags
522  *  for the modem_signals argument.  Returns 0 if successful,
523  *  -EINTR if interrupted while sleeping, or a non-zero error
524  *  returned by usb_submit_urb.
525  */
526 
527 static int digi_set_modem_signals(struct usb_serial_port *port,
528 	unsigned int modem_signals, int interruptible)
529 {
530 
531 	int ret;
532 	struct digi_port *port_priv = usb_get_serial_port_data(port);
533 	struct usb_serial_port *oob_port = (struct usb_serial_port *) ((struct digi_serial *)(usb_get_serial_data(port->serial)))->ds_oob_port;
534 	struct digi_port *oob_priv = usb_get_serial_port_data(oob_port);
535 	unsigned char *data = oob_port->write_urb->transfer_buffer;
536 	unsigned long flags = 0;
537 
538 
539 	dev_dbg(&port->dev,
540 		"digi_set_modem_signals: TOP: port=%d, modem_signals=0x%x\n",
541 		port_priv->dp_port_num, modem_signals);
542 
543 	spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
544 	spin_lock(&port_priv->dp_port_lock);
545 
546 	while (oob_priv->dp_write_urb_in_use) {
547 		spin_unlock(&port_priv->dp_port_lock);
548 		cond_wait_interruptible_timeout_irqrestore(
549 			&oob_port->write_wait, DIGI_RETRY_TIMEOUT,
550 			&oob_priv->dp_port_lock, flags);
551 		if (interruptible && signal_pending(current))
552 			return -EINTR;
553 		spin_lock_irqsave(&oob_priv->dp_port_lock, flags);
554 		spin_lock(&port_priv->dp_port_lock);
555 	}
556 	data[0] = DIGI_CMD_SET_DTR_SIGNAL;
557 	data[1] = port_priv->dp_port_num;
558 	data[2] = (modem_signals & TIOCM_DTR) ?
559 					DIGI_DTR_ACTIVE : DIGI_DTR_INACTIVE;
560 	data[3] = 0;
561 	data[4] = DIGI_CMD_SET_RTS_SIGNAL;
562 	data[5] = port_priv->dp_port_num;
563 	data[6] = (modem_signals & TIOCM_RTS) ?
564 					DIGI_RTS_ACTIVE : DIGI_RTS_INACTIVE;
565 	data[7] = 0;
566 
567 	oob_port->write_urb->transfer_buffer_length = 8;
568 
569 	ret = usb_submit_urb(oob_port->write_urb, GFP_ATOMIC);
570 	if (ret == 0) {
571 		oob_priv->dp_write_urb_in_use = 1;
572 		port_priv->dp_modem_signals =
573 			(port_priv->dp_modem_signals&~(TIOCM_DTR|TIOCM_RTS))
574 			| (modem_signals&(TIOCM_DTR|TIOCM_RTS));
575 	}
576 	spin_unlock(&port_priv->dp_port_lock);
577 	spin_unlock_irqrestore(&oob_priv->dp_port_lock, flags);
578 	if (ret)
579 		dev_err(&port->dev, "%s: usb_submit_urb failed, ret=%d\n",
580 			__func__, ret);
581 	return ret;
582 }
583 
584 /*
585  *  Digi Transmit Idle
586  *
587  *  Digi transmit idle waits, up to timeout ticks, for the transmitter
588  *  to go idle.  It returns 0 if successful or a negative error.
589  *
590  *  There are race conditions here if more than one process is calling
591  *  digi_transmit_idle on the same port at the same time.  However, this
592  *  is only called from close, and only one process can be in close on a
593  *  port at a time, so its ok.
594  */
595 
596 static int digi_transmit_idle(struct usb_serial_port *port,
597 	unsigned long timeout)
598 {
599 	int ret;
600 	unsigned char buf[2];
601 	struct digi_port *priv = usb_get_serial_port_data(port);
602 	unsigned long flags = 0;
603 
604 	spin_lock_irqsave(&priv->dp_port_lock, flags);
605 	priv->dp_transmit_idle = 0;
606 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
607 
608 	buf[0] = DIGI_CMD_TRANSMIT_IDLE;
609 	buf[1] = 0;
610 
611 	timeout += jiffies;
612 
613 	ret = digi_write_inb_command(port, buf, 2, timeout - jiffies);
614 	if (ret != 0)
615 		return ret;
616 
617 	spin_lock_irqsave(&priv->dp_port_lock, flags);
618 
619 	while (time_before(jiffies, timeout) && !priv->dp_transmit_idle) {
620 		cond_wait_interruptible_timeout_irqrestore(
621 			&priv->dp_transmit_idle_wait, DIGI_RETRY_TIMEOUT,
622 			&priv->dp_port_lock, flags);
623 		if (signal_pending(current))
624 			return -EINTR;
625 		spin_lock_irqsave(&priv->dp_port_lock, flags);
626 	}
627 	priv->dp_transmit_idle = 0;
628 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
629 	return 0;
630 
631 }
632 
633 
634 static void digi_rx_throttle(struct tty_struct *tty)
635 {
636 	unsigned long flags;
637 	struct usb_serial_port *port = tty->driver_data;
638 	struct digi_port *priv = usb_get_serial_port_data(port);
639 
640 	/* stop receiving characters by not resubmitting the read urb */
641 	spin_lock_irqsave(&priv->dp_port_lock, flags);
642 	priv->dp_throttled = 1;
643 	priv->dp_throttle_restart = 0;
644 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
645 }
646 
647 
648 static void digi_rx_unthrottle(struct tty_struct *tty)
649 {
650 	int ret = 0;
651 	unsigned long flags;
652 	struct usb_serial_port *port = tty->driver_data;
653 	struct digi_port *priv = usb_get_serial_port_data(port);
654 
655 	spin_lock_irqsave(&priv->dp_port_lock, flags);
656 
657 	/* restart read chain */
658 	if (priv->dp_throttle_restart)
659 		ret = usb_submit_urb(port->read_urb, GFP_ATOMIC);
660 
661 	/* turn throttle off */
662 	priv->dp_throttled = 0;
663 	priv->dp_throttle_restart = 0;
664 
665 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
666 
667 	if (ret)
668 		dev_err(&port->dev,
669 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
670 			__func__, ret, priv->dp_port_num);
671 }
672 
673 
674 static void digi_set_termios(struct tty_struct *tty,
675 		struct usb_serial_port *port, struct ktermios *old_termios)
676 {
677 	struct digi_port *priv = usb_get_serial_port_data(port);
678 	struct device *dev = &port->dev;
679 	unsigned int iflag = tty->termios.c_iflag;
680 	unsigned int cflag = tty->termios.c_cflag;
681 	unsigned int old_iflag = old_termios->c_iflag;
682 	unsigned int old_cflag = old_termios->c_cflag;
683 	unsigned char buf[32];
684 	unsigned int modem_signals;
685 	int arg, ret;
686 	int i = 0;
687 	speed_t baud;
688 
689 	dev_dbg(dev,
690 		"digi_set_termios: TOP: port=%d, iflag=0x%x, old_iflag=0x%x, cflag=0x%x, old_cflag=0x%x\n",
691 		priv->dp_port_num, iflag, old_iflag, cflag, old_cflag);
692 
693 	/* set baud rate */
694 	baud = tty_get_baud_rate(tty);
695 	if (baud != tty_termios_baud_rate(old_termios)) {
696 		arg = -1;
697 
698 		/* reassert DTR and (maybe) RTS on transition from B0 */
699 		if ((old_cflag&CBAUD) == B0) {
700 			/* don't set RTS if using hardware flow control */
701 			/* and throttling input */
702 			modem_signals = TIOCM_DTR;
703 			if (!(tty->termios.c_cflag & CRTSCTS) ||
704 			    !test_bit(TTY_THROTTLED, &tty->flags))
705 				modem_signals |= TIOCM_RTS;
706 			digi_set_modem_signals(port, modem_signals, 1);
707 		}
708 		switch (baud) {
709 		/* drop DTR and RTS on transition to B0 */
710 		case 0: digi_set_modem_signals(port, 0, 1); break;
711 		case 50: arg = DIGI_BAUD_50; break;
712 		case 75: arg = DIGI_BAUD_75; break;
713 		case 110: arg = DIGI_BAUD_110; break;
714 		case 150: arg = DIGI_BAUD_150; break;
715 		case 200: arg = DIGI_BAUD_200; break;
716 		case 300: arg = DIGI_BAUD_300; break;
717 		case 600: arg = DIGI_BAUD_600; break;
718 		case 1200: arg = DIGI_BAUD_1200; break;
719 		case 1800: arg = DIGI_BAUD_1800; break;
720 		case 2400: arg = DIGI_BAUD_2400; break;
721 		case 4800: arg = DIGI_BAUD_4800; break;
722 		case 9600: arg = DIGI_BAUD_9600; break;
723 		case 19200: arg = DIGI_BAUD_19200; break;
724 		case 38400: arg = DIGI_BAUD_38400; break;
725 		case 57600: arg = DIGI_BAUD_57600; break;
726 		case 115200: arg = DIGI_BAUD_115200; break;
727 		case 230400: arg = DIGI_BAUD_230400; break;
728 		case 460800: arg = DIGI_BAUD_460800; break;
729 		default:
730 			arg = DIGI_BAUD_9600;
731 			baud = 9600;
732 			break;
733 		}
734 		if (arg != -1) {
735 			buf[i++] = DIGI_CMD_SET_BAUD_RATE;
736 			buf[i++] = priv->dp_port_num;
737 			buf[i++] = arg;
738 			buf[i++] = 0;
739 		}
740 	}
741 	/* set parity */
742 	tty->termios.c_cflag &= ~CMSPAR;
743 
744 	if ((cflag&(PARENB|PARODD)) != (old_cflag&(PARENB|PARODD))) {
745 		if (cflag&PARENB) {
746 			if (cflag&PARODD)
747 				arg = DIGI_PARITY_ODD;
748 			else
749 				arg = DIGI_PARITY_EVEN;
750 		} else {
751 			arg = DIGI_PARITY_NONE;
752 		}
753 		buf[i++] = DIGI_CMD_SET_PARITY;
754 		buf[i++] = priv->dp_port_num;
755 		buf[i++] = arg;
756 		buf[i++] = 0;
757 	}
758 	/* set word size */
759 	if ((cflag&CSIZE) != (old_cflag&CSIZE)) {
760 		arg = -1;
761 		switch (cflag&CSIZE) {
762 		case CS5: arg = DIGI_WORD_SIZE_5; break;
763 		case CS6: arg = DIGI_WORD_SIZE_6; break;
764 		case CS7: arg = DIGI_WORD_SIZE_7; break;
765 		case CS8: arg = DIGI_WORD_SIZE_8; break;
766 		default:
767 			dev_dbg(dev,
768 				"digi_set_termios: can't handle word size %d\n",
769 				(cflag&CSIZE));
770 			break;
771 		}
772 
773 		if (arg != -1) {
774 			buf[i++] = DIGI_CMD_SET_WORD_SIZE;
775 			buf[i++] = priv->dp_port_num;
776 			buf[i++] = arg;
777 			buf[i++] = 0;
778 		}
779 
780 	}
781 
782 	/* set stop bits */
783 	if ((cflag&CSTOPB) != (old_cflag&CSTOPB)) {
784 
785 		if ((cflag&CSTOPB))
786 			arg = DIGI_STOP_BITS_2;
787 		else
788 			arg = DIGI_STOP_BITS_1;
789 
790 		buf[i++] = DIGI_CMD_SET_STOP_BITS;
791 		buf[i++] = priv->dp_port_num;
792 		buf[i++] = arg;
793 		buf[i++] = 0;
794 
795 	}
796 
797 	/* set input flow control */
798 	if ((iflag&IXOFF) != (old_iflag&IXOFF)
799 	    || (cflag&CRTSCTS) != (old_cflag&CRTSCTS)) {
800 		arg = 0;
801 		if (iflag&IXOFF)
802 			arg |= DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
803 		else
804 			arg &= ~DIGI_INPUT_FLOW_CONTROL_XON_XOFF;
805 
806 		if (cflag&CRTSCTS) {
807 			arg |= DIGI_INPUT_FLOW_CONTROL_RTS;
808 
809 			/* On USB-4 it is necessary to assert RTS prior */
810 			/* to selecting RTS input flow control.  */
811 			buf[i++] = DIGI_CMD_SET_RTS_SIGNAL;
812 			buf[i++] = priv->dp_port_num;
813 			buf[i++] = DIGI_RTS_ACTIVE;
814 			buf[i++] = 0;
815 
816 		} else {
817 			arg &= ~DIGI_INPUT_FLOW_CONTROL_RTS;
818 		}
819 		buf[i++] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
820 		buf[i++] = priv->dp_port_num;
821 		buf[i++] = arg;
822 		buf[i++] = 0;
823 	}
824 
825 	/* set output flow control */
826 	if ((iflag & IXON) != (old_iflag & IXON)
827 	    || (cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
828 		arg = 0;
829 		if (iflag & IXON)
830 			arg |= DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
831 		else
832 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_XON_XOFF;
833 
834 		if (cflag & CRTSCTS) {
835 			arg |= DIGI_OUTPUT_FLOW_CONTROL_CTS;
836 		} else {
837 			arg &= ~DIGI_OUTPUT_FLOW_CONTROL_CTS;
838 			tty->hw_stopped = 0;
839 		}
840 
841 		buf[i++] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
842 		buf[i++] = priv->dp_port_num;
843 		buf[i++] = arg;
844 		buf[i++] = 0;
845 	}
846 
847 	/* set receive enable/disable */
848 	if ((cflag & CREAD) != (old_cflag & CREAD)) {
849 		if (cflag & CREAD)
850 			arg = DIGI_ENABLE;
851 		else
852 			arg = DIGI_DISABLE;
853 
854 		buf[i++] = DIGI_CMD_RECEIVE_ENABLE;
855 		buf[i++] = priv->dp_port_num;
856 		buf[i++] = arg;
857 		buf[i++] = 0;
858 	}
859 	ret = digi_write_oob_command(port, buf, i, 1);
860 	if (ret != 0)
861 		dev_dbg(dev, "digi_set_termios: write oob failed, ret=%d\n", ret);
862 	tty_encode_baud_rate(tty, baud, baud);
863 }
864 
865 
866 static void digi_break_ctl(struct tty_struct *tty, int break_state)
867 {
868 	struct usb_serial_port *port = tty->driver_data;
869 	unsigned char buf[4];
870 
871 	buf[0] = DIGI_CMD_BREAK_CONTROL;
872 	buf[1] = 2;				/* length */
873 	buf[2] = break_state ? 1 : 0;
874 	buf[3] = 0;				/* pad */
875 	digi_write_inb_command(port, buf, 4, 0);
876 }
877 
878 
879 static int digi_tiocmget(struct tty_struct *tty)
880 {
881 	struct usb_serial_port *port = tty->driver_data;
882 	struct digi_port *priv = usb_get_serial_port_data(port);
883 	unsigned int val;
884 	unsigned long flags;
885 
886 	spin_lock_irqsave(&priv->dp_port_lock, flags);
887 	val = priv->dp_modem_signals;
888 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
889 	return val;
890 }
891 
892 
893 static int digi_tiocmset(struct tty_struct *tty,
894 					unsigned int set, unsigned int clear)
895 {
896 	struct usb_serial_port *port = tty->driver_data;
897 	struct digi_port *priv = usb_get_serial_port_data(port);
898 	unsigned int val;
899 	unsigned long flags;
900 
901 	spin_lock_irqsave(&priv->dp_port_lock, flags);
902 	val = (priv->dp_modem_signals & ~clear) | set;
903 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
904 	return digi_set_modem_signals(port, val, 1);
905 }
906 
907 
908 static int digi_write(struct tty_struct *tty, struct usb_serial_port *port,
909 					const unsigned char *buf, int count)
910 {
911 
912 	int ret, data_len, new_len;
913 	struct digi_port *priv = usb_get_serial_port_data(port);
914 	unsigned char *data = port->write_urb->transfer_buffer;
915 	unsigned long flags = 0;
916 
917 	dev_dbg(&port->dev,
918 		"digi_write: TOP: port=%d, count=%d, in_interrupt=%ld\n",
919 		priv->dp_port_num, count, in_interrupt());
920 
921 	/* copy user data (which can sleep) before getting spin lock */
922 	count = min(count, port->bulk_out_size-2);
923 	count = min(64, count);
924 
925 	/* be sure only one write proceeds at a time */
926 	/* there are races on the port private buffer */
927 	spin_lock_irqsave(&priv->dp_port_lock, flags);
928 
929 	/* wait for urb status clear to submit another urb */
930 	if (priv->dp_write_urb_in_use) {
931 		/* buffer data if count is 1 (probably put_char) if possible */
932 		if (count == 1 && priv->dp_out_buf_len < DIGI_OUT_BUF_SIZE) {
933 			priv->dp_out_buf[priv->dp_out_buf_len++] = *buf;
934 			new_len = 1;
935 		} else {
936 			new_len = 0;
937 		}
938 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
939 		return new_len;
940 	}
941 
942 	/* allow space for any buffered data and for new data, up to */
943 	/* transfer buffer size - 2 (for command and length bytes) */
944 	new_len = min(count, port->bulk_out_size-2-priv->dp_out_buf_len);
945 	data_len = new_len + priv->dp_out_buf_len;
946 
947 	if (data_len == 0) {
948 		spin_unlock_irqrestore(&priv->dp_port_lock, flags);
949 		return 0;
950 	}
951 
952 	port->write_urb->transfer_buffer_length = data_len+2;
953 
954 	*data++ = DIGI_CMD_SEND_DATA;
955 	*data++ = data_len;
956 
957 	/* copy in buffered data first */
958 	memcpy(data, priv->dp_out_buf, priv->dp_out_buf_len);
959 	data += priv->dp_out_buf_len;
960 
961 	/* copy in new data */
962 	memcpy(data, buf, new_len);
963 
964 	ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
965 	if (ret == 0) {
966 		priv->dp_write_urb_in_use = 1;
967 		ret = new_len;
968 		priv->dp_out_buf_len = 0;
969 	}
970 
971 	/* return length of new data written, or error */
972 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
973 	if (ret < 0)
974 		dev_err_console(port,
975 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
976 			__func__, ret, priv->dp_port_num);
977 	dev_dbg(&port->dev, "digi_write: returning %d\n", ret);
978 	return ret;
979 
980 }
981 
982 static void digi_write_bulk_callback(struct urb *urb)
983 {
984 
985 	struct usb_serial_port *port = urb->context;
986 	struct usb_serial *serial;
987 	struct digi_port *priv;
988 	struct digi_serial *serial_priv;
989 	int ret = 0;
990 	int status = urb->status;
991 
992 	/* port and serial sanity check */
993 	if (port == NULL || (priv = usb_get_serial_port_data(port)) == NULL) {
994 		pr_err("%s: port or port->private is NULL, status=%d\n",
995 			__func__, status);
996 		return;
997 	}
998 	serial = port->serial;
999 	if (serial == NULL || (serial_priv = usb_get_serial_data(serial)) == NULL) {
1000 		dev_err(&port->dev,
1001 			"%s: serial or serial->private is NULL, status=%d\n",
1002 			__func__, status);
1003 		return;
1004 	}
1005 
1006 	/* handle oob callback */
1007 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
1008 		dev_dbg(&port->dev, "digi_write_bulk_callback: oob callback\n");
1009 		spin_lock(&priv->dp_port_lock);
1010 		priv->dp_write_urb_in_use = 0;
1011 		wake_up_interruptible(&port->write_wait);
1012 		spin_unlock(&priv->dp_port_lock);
1013 		return;
1014 	}
1015 
1016 	/* try to send any buffered data on this port */
1017 	spin_lock(&priv->dp_port_lock);
1018 	priv->dp_write_urb_in_use = 0;
1019 	if (priv->dp_out_buf_len > 0) {
1020 		*((unsigned char *)(port->write_urb->transfer_buffer))
1021 			= (unsigned char)DIGI_CMD_SEND_DATA;
1022 		*((unsigned char *)(port->write_urb->transfer_buffer) + 1)
1023 			= (unsigned char)priv->dp_out_buf_len;
1024 		port->write_urb->transfer_buffer_length =
1025 						priv->dp_out_buf_len + 2;
1026 		memcpy(port->write_urb->transfer_buffer + 2, priv->dp_out_buf,
1027 			priv->dp_out_buf_len);
1028 		ret = usb_submit_urb(port->write_urb, GFP_ATOMIC);
1029 		if (ret == 0) {
1030 			priv->dp_write_urb_in_use = 1;
1031 			priv->dp_out_buf_len = 0;
1032 		}
1033 	}
1034 	/* wake up processes sleeping on writes immediately */
1035 	tty_port_tty_wakeup(&port->port);
1036 	/* also queue up a wakeup at scheduler time, in case we */
1037 	/* lost the race in write_chan(). */
1038 	schedule_work(&priv->dp_wakeup_work);
1039 
1040 	spin_unlock(&priv->dp_port_lock);
1041 	if (ret && ret != -EPERM)
1042 		dev_err_console(port,
1043 			"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1044 			__func__, ret, priv->dp_port_num);
1045 }
1046 
1047 static int digi_write_room(struct tty_struct *tty)
1048 {
1049 	struct usb_serial_port *port = tty->driver_data;
1050 	struct digi_port *priv = usb_get_serial_port_data(port);
1051 	int room;
1052 	unsigned long flags = 0;
1053 
1054 	spin_lock_irqsave(&priv->dp_port_lock, flags);
1055 
1056 	if (priv->dp_write_urb_in_use)
1057 		room = 0;
1058 	else
1059 		room = port->bulk_out_size - 2 - priv->dp_out_buf_len;
1060 
1061 	spin_unlock_irqrestore(&priv->dp_port_lock, flags);
1062 	dev_dbg(&port->dev, "digi_write_room: port=%d, room=%d\n", priv->dp_port_num, room);
1063 	return room;
1064 
1065 }
1066 
1067 static int digi_chars_in_buffer(struct tty_struct *tty)
1068 {
1069 	struct usb_serial_port *port = tty->driver_data;
1070 	struct digi_port *priv = usb_get_serial_port_data(port);
1071 
1072 	if (priv->dp_write_urb_in_use) {
1073 		dev_dbg(&port->dev, "digi_chars_in_buffer: port=%d, chars=%d\n",
1074 			priv->dp_port_num, port->bulk_out_size - 2);
1075 		/* return(port->bulk_out_size - 2); */
1076 		return 256;
1077 	} else {
1078 		dev_dbg(&port->dev, "digi_chars_in_buffer: port=%d, chars=%d\n",
1079 			priv->dp_port_num, priv->dp_out_buf_len);
1080 		return priv->dp_out_buf_len;
1081 	}
1082 
1083 }
1084 
1085 static void digi_dtr_rts(struct usb_serial_port *port, int on)
1086 {
1087 	/* Adjust DTR and RTS */
1088 	digi_set_modem_signals(port, on * (TIOCM_DTR|TIOCM_RTS), 1);
1089 }
1090 
1091 static int digi_open(struct tty_struct *tty, struct usb_serial_port *port)
1092 {
1093 	int ret;
1094 	unsigned char buf[32];
1095 	struct digi_port *priv = usb_get_serial_port_data(port);
1096 	struct ktermios not_termios;
1097 
1098 	/* be sure the device is started up */
1099 	if (digi_startup_device(port->serial) != 0)
1100 		return -ENXIO;
1101 
1102 	/* read modem signals automatically whenever they change */
1103 	buf[0] = DIGI_CMD_READ_INPUT_SIGNALS;
1104 	buf[1] = priv->dp_port_num;
1105 	buf[2] = DIGI_ENABLE;
1106 	buf[3] = 0;
1107 
1108 	/* flush fifos */
1109 	buf[4] = DIGI_CMD_IFLUSH_FIFO;
1110 	buf[5] = priv->dp_port_num;
1111 	buf[6] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1112 	buf[7] = 0;
1113 
1114 	ret = digi_write_oob_command(port, buf, 8, 1);
1115 	if (ret != 0)
1116 		dev_dbg(&port->dev, "digi_open: write oob failed, ret=%d\n", ret);
1117 
1118 	/* set termios settings */
1119 	if (tty) {
1120 		not_termios.c_cflag = ~tty->termios.c_cflag;
1121 		not_termios.c_iflag = ~tty->termios.c_iflag;
1122 		digi_set_termios(tty, port, &not_termios);
1123 	}
1124 	return 0;
1125 }
1126 
1127 
1128 static void digi_close(struct usb_serial_port *port)
1129 {
1130 	DEFINE_WAIT(wait);
1131 	int ret;
1132 	unsigned char buf[32];
1133 	struct digi_port *priv = usb_get_serial_port_data(port);
1134 
1135 	mutex_lock(&port->serial->disc_mutex);
1136 	/* if disconnected, just clear flags */
1137 	if (port->serial->disconnected)
1138 		goto exit;
1139 
1140 	/* FIXME: Transmit idle belongs in the wait_unti_sent path */
1141 	digi_transmit_idle(port, DIGI_CLOSE_TIMEOUT);
1142 
1143 	/* disable input flow control */
1144 	buf[0] = DIGI_CMD_SET_INPUT_FLOW_CONTROL;
1145 	buf[1] = priv->dp_port_num;
1146 	buf[2] = DIGI_DISABLE;
1147 	buf[3] = 0;
1148 
1149 	/* disable output flow control */
1150 	buf[4] = DIGI_CMD_SET_OUTPUT_FLOW_CONTROL;
1151 	buf[5] = priv->dp_port_num;
1152 	buf[6] = DIGI_DISABLE;
1153 	buf[7] = 0;
1154 
1155 	/* disable reading modem signals automatically */
1156 	buf[8] = DIGI_CMD_READ_INPUT_SIGNALS;
1157 	buf[9] = priv->dp_port_num;
1158 	buf[10] = DIGI_DISABLE;
1159 	buf[11] = 0;
1160 
1161 	/* disable receive */
1162 	buf[12] = DIGI_CMD_RECEIVE_ENABLE;
1163 	buf[13] = priv->dp_port_num;
1164 	buf[14] = DIGI_DISABLE;
1165 	buf[15] = 0;
1166 
1167 	/* flush fifos */
1168 	buf[16] = DIGI_CMD_IFLUSH_FIFO;
1169 	buf[17] = priv->dp_port_num;
1170 	buf[18] = DIGI_FLUSH_TX | DIGI_FLUSH_RX;
1171 	buf[19] = 0;
1172 
1173 	ret = digi_write_oob_command(port, buf, 20, 0);
1174 	if (ret != 0)
1175 		dev_dbg(&port->dev, "digi_close: write oob failed, ret=%d\n",
1176 									ret);
1177 	/* wait for final commands on oob port to complete */
1178 	prepare_to_wait(&priv->dp_flush_wait, &wait,
1179 			TASK_INTERRUPTIBLE);
1180 	schedule_timeout(DIGI_CLOSE_TIMEOUT);
1181 	finish_wait(&priv->dp_flush_wait, &wait);
1182 
1183 	/* shutdown any outstanding bulk writes */
1184 	usb_kill_urb(port->write_urb);
1185 exit:
1186 	spin_lock_irq(&priv->dp_port_lock);
1187 	priv->dp_write_urb_in_use = 0;
1188 	wake_up_interruptible(&priv->dp_close_wait);
1189 	spin_unlock_irq(&priv->dp_port_lock);
1190 	mutex_unlock(&port->serial->disc_mutex);
1191 }
1192 
1193 
1194 /*
1195  *  Digi Startup Device
1196  *
1197  *  Starts reads on all ports.  Must be called AFTER startup, with
1198  *  urbs initialized.  Returns 0 if successful, non-zero error otherwise.
1199  */
1200 
1201 static int digi_startup_device(struct usb_serial *serial)
1202 {
1203 	int i, ret = 0;
1204 	struct digi_serial *serial_priv = usb_get_serial_data(serial);
1205 	struct usb_serial_port *port;
1206 
1207 	/* be sure this happens exactly once */
1208 	spin_lock(&serial_priv->ds_serial_lock);
1209 	if (serial_priv->ds_device_started) {
1210 		spin_unlock(&serial_priv->ds_serial_lock);
1211 		return 0;
1212 	}
1213 	serial_priv->ds_device_started = 1;
1214 	spin_unlock(&serial_priv->ds_serial_lock);
1215 
1216 	/* start reading from each bulk in endpoint for the device */
1217 	/* set USB_DISABLE_SPD flag for write bulk urbs */
1218 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1219 		port = serial->port[i];
1220 		ret = usb_submit_urb(port->read_urb, GFP_KERNEL);
1221 		if (ret != 0) {
1222 			dev_err(&port->dev,
1223 				"%s: usb_submit_urb failed, ret=%d, port=%d\n",
1224 				__func__, ret, i);
1225 			break;
1226 		}
1227 	}
1228 	return ret;
1229 }
1230 
1231 static int digi_port_init(struct usb_serial_port *port, unsigned port_num)
1232 {
1233 	struct digi_port *priv;
1234 
1235 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1236 	if (!priv)
1237 		return -ENOMEM;
1238 
1239 	spin_lock_init(&priv->dp_port_lock);
1240 	priv->dp_port_num = port_num;
1241 	init_waitqueue_head(&priv->dp_transmit_idle_wait);
1242 	init_waitqueue_head(&priv->dp_flush_wait);
1243 	init_waitqueue_head(&priv->dp_close_wait);
1244 	INIT_WORK(&priv->dp_wakeup_work, digi_wakeup_write_lock);
1245 	priv->dp_port = port;
1246 
1247 	init_waitqueue_head(&port->write_wait);
1248 
1249 	usb_set_serial_port_data(port, priv);
1250 
1251 	return 0;
1252 }
1253 
1254 static int digi_startup(struct usb_serial *serial)
1255 {
1256 	struct digi_serial *serial_priv;
1257 	int ret;
1258 
1259 	serial_priv = kzalloc(sizeof(*serial_priv), GFP_KERNEL);
1260 	if (!serial_priv)
1261 		return -ENOMEM;
1262 
1263 	spin_lock_init(&serial_priv->ds_serial_lock);
1264 	serial_priv->ds_oob_port_num = serial->type->num_ports;
1265 	serial_priv->ds_oob_port = serial->port[serial_priv->ds_oob_port_num];
1266 
1267 	ret = digi_port_init(serial_priv->ds_oob_port,
1268 						serial_priv->ds_oob_port_num);
1269 	if (ret) {
1270 		kfree(serial_priv);
1271 		return ret;
1272 	}
1273 
1274 	usb_set_serial_data(serial, serial_priv);
1275 
1276 	return 0;
1277 }
1278 
1279 
1280 static void digi_disconnect(struct usb_serial *serial)
1281 {
1282 	int i;
1283 
1284 	/* stop reads and writes on all ports */
1285 	for (i = 0; i < serial->type->num_ports + 1; i++) {
1286 		usb_kill_urb(serial->port[i]->read_urb);
1287 		usb_kill_urb(serial->port[i]->write_urb);
1288 	}
1289 }
1290 
1291 
1292 static void digi_release(struct usb_serial *serial)
1293 {
1294 	struct digi_serial *serial_priv;
1295 	struct digi_port *priv;
1296 
1297 	serial_priv = usb_get_serial_data(serial);
1298 
1299 	priv = usb_get_serial_port_data(serial_priv->ds_oob_port);
1300 	kfree(priv);
1301 
1302 	kfree(serial_priv);
1303 }
1304 
1305 static int digi_port_probe(struct usb_serial_port *port)
1306 {
1307 	unsigned port_num;
1308 
1309 	port_num = port->number - port->serial->minor;
1310 
1311 	return digi_port_init(port, port_num);
1312 }
1313 
1314 static int digi_port_remove(struct usb_serial_port *port)
1315 {
1316 	struct digi_port *priv;
1317 
1318 	priv = usb_get_serial_port_data(port);
1319 	kfree(priv);
1320 
1321 	return 0;
1322 }
1323 
1324 static void digi_read_bulk_callback(struct urb *urb)
1325 {
1326 	struct usb_serial_port *port = urb->context;
1327 	struct digi_port *priv;
1328 	struct digi_serial *serial_priv;
1329 	int ret;
1330 	int status = urb->status;
1331 
1332 	/* port sanity check, do not resubmit if port is not valid */
1333 	if (port == NULL)
1334 		return;
1335 	priv = usb_get_serial_port_data(port);
1336 	if (priv == NULL) {
1337 		dev_err(&port->dev, "%s: port->private is NULL, status=%d\n",
1338 			__func__, status);
1339 		return;
1340 	}
1341 	if (port->serial == NULL ||
1342 		(serial_priv = usb_get_serial_data(port->serial)) == NULL) {
1343 		dev_err(&port->dev, "%s: serial is bad or serial->private "
1344 			"is NULL, status=%d\n", __func__, status);
1345 		return;
1346 	}
1347 
1348 	/* do not resubmit urb if it has any status error */
1349 	if (status) {
1350 		dev_err(&port->dev,
1351 			"%s: nonzero read bulk status: status=%d, port=%d\n",
1352 			__func__, status, priv->dp_port_num);
1353 		return;
1354 	}
1355 
1356 	/* handle oob or inb callback, do not resubmit if error */
1357 	if (priv->dp_port_num == serial_priv->ds_oob_port_num) {
1358 		if (digi_read_oob_callback(urb) != 0)
1359 			return;
1360 	} else {
1361 		if (digi_read_inb_callback(urb) != 0)
1362 			return;
1363 	}
1364 
1365 	/* continue read */
1366 	ret = usb_submit_urb(urb, GFP_ATOMIC);
1367 	if (ret != 0 && ret != -EPERM) {
1368 		dev_err(&port->dev,
1369 			"%s: failed resubmitting urb, ret=%d, port=%d\n",
1370 			__func__, ret, priv->dp_port_num);
1371 	}
1372 
1373 }
1374 
1375 /*
1376  *  Digi Read INB Callback
1377  *
1378  *  Digi Read INB Callback handles reads on the in band ports, sending
1379  *  the data on to the tty subsystem.  When called we know port and
1380  *  port->private are not NULL and port->serial has been validated.
1381  *  It returns 0 if successful, 1 if successful but the port is
1382  *  throttled, and -1 if the sanity checks failed.
1383  */
1384 
1385 static int digi_read_inb_callback(struct urb *urb)
1386 {
1387 	struct usb_serial_port *port = urb->context;
1388 	struct digi_port *priv = usb_get_serial_port_data(port);
1389 	int opcode = ((unsigned char *)urb->transfer_buffer)[0];
1390 	int len = ((unsigned char *)urb->transfer_buffer)[1];
1391 	int port_status = ((unsigned char *)urb->transfer_buffer)[2];
1392 	unsigned char *data = ((unsigned char *)urb->transfer_buffer) + 3;
1393 	int flag, throttled;
1394 	int status = urb->status;
1395 
1396 	/* do not process callbacks on closed ports */
1397 	/* but do continue the read chain */
1398 	if (urb->status == -ENOENT)
1399 		return 0;
1400 
1401 	/* short/multiple packet check */
1402 	if (urb->actual_length != len + 2) {
1403 		dev_err(&port->dev, "%s: INCOMPLETE OR MULTIPLE PACKET, "
1404 			"status=%d, port=%d, opcode=%d, len=%d, "
1405 			"actual_length=%d, status=%d\n", __func__, status,
1406 			priv->dp_port_num, opcode, len, urb->actual_length,
1407 			port_status);
1408 		return -1;
1409 	}
1410 
1411 	spin_lock(&priv->dp_port_lock);
1412 
1413 	/* check for throttle; if set, do not resubmit read urb */
1414 	/* indicate the read chain needs to be restarted on unthrottle */
1415 	throttled = priv->dp_throttled;
1416 	if (throttled)
1417 		priv->dp_throttle_restart = 1;
1418 
1419 	/* receive data */
1420 	if (opcode == DIGI_CMD_RECEIVE_DATA) {
1421 		/* get flag from port_status */
1422 		flag = 0;
1423 
1424 		/* overrun is special, not associated with a char */
1425 		if (port_status & DIGI_OVERRUN_ERROR)
1426 			tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
1427 
1428 		/* break takes precedence over parity, */
1429 		/* which takes precedence over framing errors */
1430 		if (port_status & DIGI_BREAK_ERROR)
1431 			flag = TTY_BREAK;
1432 		else if (port_status & DIGI_PARITY_ERROR)
1433 			flag = TTY_PARITY;
1434 		else if (port_status & DIGI_FRAMING_ERROR)
1435 			flag = TTY_FRAME;
1436 
1437 		/* data length is len-1 (one byte of len is port_status) */
1438 		--len;
1439 		if (len > 0) {
1440 			tty_insert_flip_string_fixed_flag(&port->port, data,
1441 					flag, len);
1442 			tty_flip_buffer_push(&port->port);
1443 		}
1444 	}
1445 	spin_unlock(&priv->dp_port_lock);
1446 
1447 	if (opcode == DIGI_CMD_RECEIVE_DISABLE)
1448 		dev_dbg(&port->dev, "%s: got RECEIVE_DISABLE\n", __func__);
1449 	else if (opcode != DIGI_CMD_RECEIVE_DATA)
1450 		dev_dbg(&port->dev, "%s: unknown opcode: %d\n", __func__, opcode);
1451 
1452 	return throttled ? 1 : 0;
1453 
1454 }
1455 
1456 
1457 /*
1458  *  Digi Read OOB Callback
1459  *
1460  *  Digi Read OOB Callback handles reads on the out of band port.
1461  *  When called we know port and port->private are not NULL and
1462  *  the port->serial is valid.  It returns 0 if successful, and
1463  *  -1 if the sanity checks failed.
1464  */
1465 
1466 static int digi_read_oob_callback(struct urb *urb)
1467 {
1468 
1469 	struct usb_serial_port *port = urb->context;
1470 	struct usb_serial *serial = port->serial;
1471 	struct tty_struct *tty;
1472 	struct digi_port *priv = usb_get_serial_port_data(port);
1473 	int opcode, line, status, val;
1474 	int i;
1475 	unsigned int rts;
1476 
1477 	/* handle each oob command */
1478 	for (i = 0; i < urb->actual_length - 3;) {
1479 		opcode = ((unsigned char *)urb->transfer_buffer)[i++];
1480 		line = ((unsigned char *)urb->transfer_buffer)[i++];
1481 		status = ((unsigned char *)urb->transfer_buffer)[i++];
1482 		val = ((unsigned char *)urb->transfer_buffer)[i++];
1483 
1484 		dev_dbg(&port->dev, "digi_read_oob_callback: opcode=%d, line=%d, status=%d, val=%d\n",
1485 			opcode, line, status, val);
1486 
1487 		if (status != 0 || line >= serial->type->num_ports)
1488 			continue;
1489 
1490 		port = serial->port[line];
1491 
1492 		priv = usb_get_serial_port_data(port);
1493 		if (priv == NULL)
1494 			return -1;
1495 
1496 		tty = tty_port_tty_get(&port->port);
1497 
1498 		rts = 0;
1499 		if (tty)
1500 			rts = tty->termios.c_cflag & CRTSCTS;
1501 
1502 		if (tty && opcode == DIGI_CMD_READ_INPUT_SIGNALS) {
1503 			spin_lock(&priv->dp_port_lock);
1504 			/* convert from digi flags to termiox flags */
1505 			if (val & DIGI_READ_INPUT_SIGNALS_CTS) {
1506 				priv->dp_modem_signals |= TIOCM_CTS;
1507 				/* port must be open to use tty struct */
1508 				if (rts) {
1509 					tty->hw_stopped = 0;
1510 					tty_port_tty_wakeup(&port->port);
1511 				}
1512 			} else {
1513 				priv->dp_modem_signals &= ~TIOCM_CTS;
1514 				/* port must be open to use tty struct */
1515 				if (rts)
1516 					tty->hw_stopped = 1;
1517 			}
1518 			if (val & DIGI_READ_INPUT_SIGNALS_DSR)
1519 				priv->dp_modem_signals |= TIOCM_DSR;
1520 			else
1521 				priv->dp_modem_signals &= ~TIOCM_DSR;
1522 			if (val & DIGI_READ_INPUT_SIGNALS_RI)
1523 				priv->dp_modem_signals |= TIOCM_RI;
1524 			else
1525 				priv->dp_modem_signals &= ~TIOCM_RI;
1526 			if (val & DIGI_READ_INPUT_SIGNALS_DCD)
1527 				priv->dp_modem_signals |= TIOCM_CD;
1528 			else
1529 				priv->dp_modem_signals &= ~TIOCM_CD;
1530 
1531 			spin_unlock(&priv->dp_port_lock);
1532 		} else if (opcode == DIGI_CMD_TRANSMIT_IDLE) {
1533 			spin_lock(&priv->dp_port_lock);
1534 			priv->dp_transmit_idle = 1;
1535 			wake_up_interruptible(&priv->dp_transmit_idle_wait);
1536 			spin_unlock(&priv->dp_port_lock);
1537 		} else if (opcode == DIGI_CMD_IFLUSH_FIFO) {
1538 			wake_up_interruptible(&priv->dp_flush_wait);
1539 		}
1540 		tty_kref_put(tty);
1541 	}
1542 	return 0;
1543 
1544 }
1545 
1546 module_usb_serial_driver(serial_drivers, id_table_combined);
1547 
1548 MODULE_AUTHOR(DRIVER_AUTHOR);
1549 MODULE_DESCRIPTION(DRIVER_DESC);
1550 MODULE_LICENSE("GPL");
1551